What is the best practice for recommissioning my phone?

Running IT for a small nonprofit that provides phones for several staff members. When people leave, we've been removing their Google account from the phone, uninstalling any apps they personally added (leaving installed the ones we want the next user to have), and then handing the phone off to the next user. Does this make for a clean hand-off, or is there something else we should be doing to ensure that the next user doesn't have access to the first user's data?